Sherlock has a Little Brother?
by IzzyDelta
Summary: A one shot about why Sherlock loathes Anderson so much. Also it explores why Anderson is so stupid but Mycroft and Sherlock are so smart.


**Sherlock Has A Little Brother?**

Sherlock Holmes surveys the crime scene from behind the tape. He sneers as his eyes pass over Anderson and Donovan standing to one side talking quietly. Sherlock makes eye contact with DI Lestrade who nods and Sherlock ducks under the tape and strolls around to view the scene from different angles. John Watson follows him under the tape but waits for Sherlock to need him to confirm cause and time of death. Anderson watches as Sherlock does his job for him.

'Oh look the freak and his handler.' Anderson growls. Sherlock freezes for a tiny moment but carries on regardless. John growls deep in his throat. He carefully steps over to Lestrade.

'Only pathetic individuals take their sexual frustration out on others.' John murmurs to the DI just loud enough for Sherlock and Anderson to hear. Sherlock glances up at John with a slightly bemused expression. John fishes out his phone and texts his best friend. Sherlock reads it and smirks making the forensic technician extremely uncomfortable and nervous.

Sherlock devours the crime scene and after twenty minutes he has everything tied up and has worked out who the culprit is. Sherlock casts a final glance around the scene before ducking under the tape to leave the police to clear up. A sleek black car draws up and Sherlock groans. The door opens and Mycroft climbs out. The two brothers lock gazes and Sherlock reads the message in Mycroft's eyes that he is not the one Mycroft is looking for. 'Who?'

'Anderson.'

'Be careful brother, your IQ might get lowered if you get too close.'

'Now brother, don't be rude.' The Brothers Holmes survey all of the police officers cleaning up the crime scene and getting ready to reopen the road. 'Where is he?'

'The idiot in the white overall suit and Lego hair.'

'And the woman?'

'Donovan, could be intelligent if she stopped hanging around with him.' Mycroft raises his eyebrow at Sherlock. 'No. No Mycroft, I'm not getting him for you.'

'I'll go.' John mutters ducking back under the police tape. The two brothers watch John approach Anderson and mutters quietly to the technician. The three of them glance over at the two brothers. John walks back to his best friend and best friend's brother.

'He'll be over in a second. He wants to get the overalls off.' Mycroft nods and strolls back over to his car.

'Coming Sherlock?'

'Someone needs to protect your IQ brother.'

'Please join us John.'

'I will, he'll need someone who can deal with you two.' Sherlock smirks as he and Mycroft climb into the car. John leans against the side of the car waiting for Anderson to make his way over.

'Are you sure you don't know what's going on?' Anderson asks approaching John skittishly.

'Nope. Listen to me Anderson, don't make any comments about either of them being freaks. Mycroft is rather protective of Sherlock and can make you disappear completely. He pretty much is the government.' John opens the car door. 'Get in.' Anderson climbs in before John who closes the door behind him. Mycroft scans the forensic technician making them sit in silence for a few moments.

'I understand you have been looking for your biological parents.'

'Yes.' Anderson swallows nervously. Sherlock smirks.

'How have you got on?'

'I haven't.'

'Meaning?' Anderson hesitates.

'Anderson, just tell him straight. Chances are he already knows but wants to hear it from you. Every time you pause, hesitate or whatever you have it worse for yourself.'

'Thank you John.' Mycroft drawls, his voice dripping with sarcasm.

'My pleasure Mycroft.' John's tone is light. Anderson takes a deep breath.

'Every time I try and apply for a copy of my birth certificate, I get denied.'

'Mycroft.'

'Yes brother?'

'Why?'

'Why what?' Anderson's head swivels between the two Holmes'. John switches the focus of his gaze between the government official and the forensic technician. Mycroft glances at the doctor.

'I think the doctor understands.'

'Yes, I think I do; part of it anyway.' Mycroft smirks and withdraws a single piece of paper from his briefcase. He passes it across to Anderson, who gasps.

'How did you get this?'

'I'm sure Dr Watson has told you I am the British Government.'

'You stopped him from accessing his birth records, why?' Sherlock looks over Anderson's shoulder. 'Oh.'

'Oh, indeed.'

'Your father?'

'Of course.'

'Their father?' John sighs.

'Anderson, look at the paternal column.'

'You've seen this?'

'No, I looked between the three of you.' Anderson's expression is confused. John sighs again and decided to spell it out. 'You all share the same nose. I assume you all inherited it from your father because I've seen pictures of their mother. She looks a lot like Sherlock and not so much like Mycroft. You have nothing from her meaning that you share the same genes from their father's side. I know their parents' marriage fell apart after Sherringford Holmes committed adultery. Therefore it is pretty much safe to assume their mother found out about your birth and filed for divorce.' John leans back in his seat. 'Anderson, I'm afraid you've been insulting your own brother.'

'What? No, impossible.'

'Why do you think I hate you so much Anderson?'

'What?'

'You caused my mother so much distress she nearly took her own life, twice. Especially when _Father_ wanted to raise you in our house.'

'Mummy saw sense and when Father left to go on a business trip abroad she packed his bags, left them at the gatehouse and dumped you in an orphanage.'

'You have to stop calling me stupid then.' Anderson starts to smirk.

'No, he doesn't. Father was as thick as they come. Our intelligence is from Mother's family.' Mycroft drawls.

'Put it another way. Your mother couldn't be bothered to fight for you or look for you when you were put into the orphanage. Our mother fought tooth and nail to get everything, us, the house, the money, the assets, _everything. _Father was ruined.' Mycroft taps on the screen separating the four of them from the driver. The driver smoothly drives the car to the main road and merges into the flow of traffic.

'Where are we going?'

'My house.' Mycroft says dryly. 'I refuse to finish this conversation in a car.' Sherlock opens his mouth.

'Sherlock, don't.' John warns him before he can speak.

'How do you know what I was going to say?'

'Sherlock, I live with you. Apart from Mycroft I'm the only one who can read you.'

'Lestrade can.'

'Not as well as John little brother.'

'What was he going to say?'

'"To show you what you've lost"' Sherlock huffs and slumps in his seat. 'I was right then.'

'Yes.' Sherlock mutters into his scarf.

The next day Anderson walks into Scotland Yard and scowls at Sherlock who is already there and talking to Lestrade about the case. John acknowledges him but Anderson refuses to reciprocate. 'Oh look, the brat's arrived.' Sherlock mutters.

'I'm a brat am I freak?'

'Pretty much, an unwanted, unloved marriage breaking little brat.'

'Sherlock.' John warns. Sherlock rounds on him.

'He's lucky Mycroft threw him out yesterday. If I had, he wouldn't be walking today.'

'Your moth-' Anderson starts to say but is cut off by Sherlock seizing him by the throat and slamming against the wall.

'Mycroft has already warned you against insulting my mother. I'm going to let you go now, if you dare to even think about insulting her I will hurt you.' Sherlock drops Anderson to the floor as he steps back.

'What happened last night?' Lestrade asks.

'Anderson is the half brother of Sherlock and Mycroft. Holmes senior was, it seems, a serial adulterer.'

'He nearly killed my mother, twice.' Sherlock snarls. 'I know, I know it's irrational to blame him for her depression but answer me this if you ask a five-year-old child who's is to blame what will they say?'

'The baby.' Lestrade mutters.

'Your mother deserved to be-'

'Anderson shut up.' Lestrade gets in there. 'He's already warned you about insulting his mother.' Anderson scowls. 'Viola Holmes was the most sweetest, most caring open woman I have ever met and ever will meet.' Sherlock openly stares at the DI.

'When did?'

'When Mycroft interviewed me about you for the first time. She came in and interrupted Mycroft when he was giving me a long winded lecture about Sherlock and told him tea was ready.'

'You got the manor? I got a warehouse.' John protests astounded.

'Mycroft was trying to get me to be his flatmate.' Lestrade turns back to the nervous figure of Anderson. 'Think about insulting Viola's memory, I will personally help them hurt you.' Sherlock smirks.

'If anyone didn't deserved to be cheated on, it was my mother.' Mycroft's voice drifts across the room, making Anderson spin on his heels. 'I did warn you about insulting my mother. How is your back? You did land on it rather hard.' Anderson rubs his back and grimaces. Mycroft tosses a manila envelope onto Anderson's desk and leaves abruptly. Sherlock dives and opens it before Anderson even manages to move. Sherlock snorts and passes it to John. John glances at it and passes it on. The document inside the envelope is passed around the room and everyone is wide-eyed. Anderson snatches the document and reads it for himself. He narrows his eyes at John

'What does it mean?'

'How can he be so ignorant?' Lestrade splutters chocking on his coffee. John takes pity on the technician.

'Anderson it's a rare genetic condition. Not everyone who has it actually suffers from it. You just have to be extremely careful about what goes on. There is a theory, not proven, that it is most commonly found in the offspring of adulterers.' Sherlock smirks in triumph.

'Father had it. He died from an infection caused by the disease five years ago.' Sherlock scrawls something on a loose bit of paper. 'I don't have to like you being my brother. It will not stop me from insulting you, but here.' Sherlock throws the paper at Anderson. 'That is the name and number of the doctor who specialises in the treatment to prevent it from mutating. Try and prevent yourself from insulting my mother and I might warm up to you. But don't expect too much.'

_A/N_

_Just to let people know the genetic disease mentioned in the ending is a complete fabrication of my imagination. And I didn't want Sherlock to de entirely mean and maybe produce an opportunity for sometime in the future that Anderson and Sherlock might actually be friends – even if it is a long shot._

_Also there is potential for a sequel do people want to see Sherlock warming up to his younger brother or hear about what happened at the manor? Say in review or PM_


End file.
